Are Meteors Cool?

This post references the treat one occasionally gets when looking at the night sky and a meteor flashes through the background of stars. Some people call it a “shooting star.” Are meteors cool? Yes, seeing one is an exhilarating experience.

Where do they come from and what are they? Most are a small piece rock from an asteroid. Asteroids orbit the sun, many in the Asteroid Belt between Mars and Jupiter. Most meteors are very small and burn up in the atmosphere, which produces the familiar flash of light. Larger meteors can reach the ground, but rarely large enough to create any noticeable damage.

An estimated 18,000 to 84,000 meteors that are larger than 10 grams (roughly half an ounce for those still in that system) hit the Earth’s surface each day

About 50 tons a day are added to the Earth’s mass from meteors striking the ground and oceans.

99.8% of meteors originate as pieces of asteroids.

The remaining 0.2% of meteors blasted from the surfaces of either the Earth’s moon or Mars.

Terminology (I tend to call everything a meteor)

Meteor—small piece of an asteroid that enters the Earth’s atmosphere.

Meteorite—meteor that reaches the Earth’s surface—it lands.

Asteroid—rocky body orbiting the sun, many of which are in the asteroid belt between Mars and Jupiter.

Although a meteor is described as a small, rocky piece of an asteroid, the craters formed by large objects striking the Earth throughout history frequently are called “meteor craters.” They were certainly large enough objects to be asteroids, but I will classify them meteors anyway for the next section of this post.

Five Largest Meteor Impacts on Earth

5) The Tunguska Explosion, Siberia, Russia—We only know that something big exploded near Russia’s Tunguska River in June, 1908 that flattened over 800 square miles of forest. Instruments as far away as Great Britain detected the event. No fragments of meteorite have ever been found leading some to believe that the object was a comet. And then there are those that contend that an alien spacecraft exploded there.

4) Manicouagan Crater, Canada—Manicouagan Reservoir, known as the “Eye of Quebec,” formed 212 million years ago when a 3 mile wide asteroid hit the Earth. The passing of glaciers and erosion wore away 62-mile diameter crater but what remains is very noticeable. A circular lake rings the dry center area, appearing as if a giant mote surrounds the impact area.

3) Sudbury Basin, Ontario, Canada—The 1.85 billion year old crater is home to over 160,000 people near Sudbury, Ontario. It is 40 miles long, 16 miles wide, and 9 miles deep. A number of mining companies discovered over a century ago that the bottom is rich in nickel from the asteroid. It provides about 10% of the world’s nickel.

2) Chicxulub Crater, Mexico—One of the largest meteor strikes in Earth’s history, the asteroid the size of a small city smashed into the Yucatan Peninsula in Mexico near today’s village of Chicxulub. The force of the 65 million year old event equates to about one billion kilotons, compared to the Hiroshima bomb of 20 kilotons for reference. Leaving a 105-mile wide impact crater at that time, it created tsunamis, earthquakes, and volcanic eruptions around the world. It altered Earth’s climate, eliminating 75% of the planet’s animals, including the dinosaurs. A true extinction event that likely paved the way for human evolution.

1) Vredefort Dome, South Africa—Current record holder for largest impact crater on Earth, the six-mile-diameter asteroid hit South Africa over two billion years ago. The crater is 186 mile wide, mostly eroded, but still impressive when viewed from space. At a time prior to multi-celled life on the planet, no eyes witnessed this disaster early in the Earth’s history. We can hope that record is never broken.